Locking device for auger latches

ABSTRACT

Apparatus for connecting the locking auger sections end to end in a string of auger sections driven by an auger mining machine. Auger sections are connected end to end by inserting a shank portion of one section into a socket portion of the adjacent section and locking them by a latch bolt. The latch bolt is carried in a housing on the socket portion of one section and extends into a hole in the shank portion of the other section. The latch bolt carries a transverse locking pin and is rotatable in the housing to position the locking pin in one of two slots in the housing. One slot is of longer length axially of the bolt to permit the latch bolt to be withdrawn from the hole in the shank portion, while the other slot prevents the withdrawal of the latch bolt. The auger sections remain locked together until the latch bolt is intentionally turned to a position where the pin is in the longer slot, and the bolt is then intentionally drawn out of the shank hole.

United States Patent Young [4 1 Aug. 22, 1972 [54] LOCKING DEVICE FORAUGER Primary Examiner-Andrew V. Kundrat LATCHES AttorneyBoswonh,Sessions, Herrstrom & Cain [72] Inventor: Will|am G. Young, Salem, OhioABSTRACT [73] Asslgnee gg Tool Company Salem Apparatus for connectingthe locking auger sections end to end in a string of auger sectionsdriven by an [2 Flledi 1970 auger mining machine. Auger sections areconnected [211 App]. 98,558 end to end by inserting a shank portion ofone section into a socket portion of the ad acent section and lockingthem by a latch bolt. The latch bolt is carried U-S- CL", l9, in ahousing on of one and [51] Int. Cl ..F 16b 7/00 extends into a hole inthe shank portion f the other [58] held of Search "287/2, 1 1310- 9;248/408; section. The latch bolt carries a transverse locking pin279/76; 198/213 and is rotatable in the housing to position the lockingpin in one of two slots in the housing. One slot is of [56] ReferencesC'ted longer length axially of the bolt to permit the latch UNITEDSTATES PATENTS bolt to withdrawn from the hole in the shank pornon,while the other slot prevents the withdrawal of Anderson the latch Theauger ections remain locked 3,554,585 1/ 1971 sol'fmsen "248/408together until the latch bolt is intentionally turned to a 2,588,9013/1952 Welkartm ..287/1 19 X position where the pin is in the longerSlot, and the 1,446,430 2/ 1923 Orchowskl ..287/ l 19 bolt is thenintentionally drawn out of the Shank h]e 630,990 8/1899 Salmond..287/DlG. 9

17 Claims, 7 Drawing Figures l l E Z 45 70 20 24 3 54 62 4 7 20 29 36'46 56 32 L T 42 42a 9 36" 32 3/ 39 40 /ll V L PATENTED M1822 m2 SHEH 2BF 2 INVENTOR. WILL/AM 6. YOUNG mam LOCKING DEVICE FOR AUGER LATCI-IESBACKGROUND OF THE INVENTION This invention relates to auger miningmachines for mining coal and the like such as described in McCarthy US.Pat. No. 2,880,707, and more particularly to latching devices forretaining auger sections in such machines in end-to-end contact.

In a typical auger mining operation, the auger mining machine ispositioned adjacent a wall of earth containing a seam of coal so that astring of connected auger sections rotated and pushed by the machinepenetrates and follows the coal seam. A cutting head at the lead end ofthe auger string is thus advanced into the coal until it reaches itsmaximum depth permitted by the advance of a carriage on the machine thatrotates and advances the auger string. The auger string including thecutting head is then disconnected from the carriage which is thereafterretracted. A section of auger is then added to the string between therearmost auger section and the carriage, and the cutting head and augersections are then again advanced into the coal seam to the maximumadvance of the carriage while the auger string is rotated. Coal feedsback along the helical auger flighting of the auger string. When therearmost auger section again has reached the maximum advance permittedby the machine carriage, an additional section of auger is connectedbetween the carriage and the previous section.

The process is continued in this manner until the desired depth of holeis reached. Thereafter, the string of auger sections is withdrawn byretracting the machine carriage until the rearmost auger section clearsthe hole, removing such section, advancing the carriage and reconnectingit to the last section in the auger line, retracting the carriage toexpose another auger section, removing it, and so on.

Conventionally, each auger section is provided with a socket or femaleportion that is non-circular, and preferably square in one end and anon-circular shank or male portion of the same shape and slightlysmaller cross section at the other end. The shank fits into the femaleportion of an adjacent auger section and is retained there by a latchthat extends through a wall of the socket into a hole in the shank.

Such connections have proven to be unreliable under certain conditions,since the latch bolt may work itself free and allow the auger sectionsto become disconnected. When this occurs, torque can no longer betransmitted to the portion of the auger string and cutting head beyondthe disconnection or break in the string, and the auger sections musttherefore be reconnected if it is intended to continue drilling. When itis intended to withdraw the auger string, su'ch undesired disconnectionalso prevents withdrawal of the portion of the auger string beyond thedisconnection, unless the sections are reconnected.

Reconnecting the auger sections thus unintentionally disconnected in anauger string is extremely difficult, time consuming and expensive,particularly on machines that employ parallel dual or triple cuttingheads utilizing more than one auger string. Often all the equipment inthe hole must be removed. Thus, considerable time and danger may beinvolved, since often a man must go into the hole to reach the portionof the auger string beyond the break.

SUMMARY OF THE INVENTION A general object of this invention is toprovide latch means for connecting auger sections end-to-end thatovercomes the problems encountered with prior latch means.

A more particular object is to provide improved latch means forconnecting auger sections end-to-end that includes provision for lockingthe latch means to prevent unintentional disconnecting.

Another object of this invention is to provide a bolt and hole latch forconnecting auger sections end-toend that includes means for locking thebolt in the hole, whereby the auger sections cannot become disconnected.

Still another object is to provide improved latch means for latching andlocking auger sections end-toend that is reliable, convenient to use andinexpensive to manufacture.

A preferred form of latch means according to this invention for latchingand locking together a first auger section having a shank and a secondauger section having a longitudinally extending socket receiving theshank, includes a housing mounted on the second auger section and alatch bolt in the housing having an end protruding therefrom. Thehousing has first and second interconnected slots one of which isgenerally parallel to the latch bolt. A locking pin extends transverselythrough the latch bolt and into one of the slots. The length of theslots axially of the bolt is such that the locking pin is free to movein one of the slots at least the length of the protruding end of thelatch bolt and in the other slot substantially less than the length ofthe protruding end. The latch bolt is rotatable in the housing toposition its locking pin in one or the other of the slots. In use thelatch bolt may extend into a transverse hole in the shank and be lockedtherein or not according to whether the locking pin is positioned in oneor the other of the slots. Preferably, the latch bolt is biased, as by acompression spring, so the end moves into the hole in the shank whenaligned with the hole.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a somewhat diagrammatic sideelevation of the basic parts of an auger mining machine showing adjacentauger sections ready for end-to-end connection;

FIG. 2 is an end view in elevation of the shank end or male portion ofan auger section;

FIG. 3 is an end view in elevation of the socket end or female portionof an auger section showing the improved auger latch of this invention;

FIG. 4 is a side elevation of two auger sections latched but not lockedtogether by the improved auger latch of this invention;

FIG. 5 is a longitudinal sectional view to a larger scale of the augersections and latch of FIG. 4;

FIG. 6 is a plan view along the line 66 of FIG. 5 but to a larger scaleshowing the latch of this invention in its locked and in its unlockedposition;

FIG. 7 is a side elevation similar to FIG. 4 but showing the augersections latched and locked together.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows an auger miningmachine 1 for rotating and advancing an auger string 2 made up of augersections 3 adapted to be connected together end-to-end. Sections 3 arerotatably driven by a carriage 4 movably mounted on a base 5 of themachine for advancing and retracting movement in a straight path, in amanner and by means known in the art. The drive shaft 14 of thecarriage, connected to a suitable known power source on the carriage, isconnected through a known coupling 15 to the rear end of the augerstring for rotating it.

The leading end of the leading auger section 3 carries a cutting head 17of a suitable known type. The auger sections 3 are conventional exceptfor the latch means of the invention; each section comprises a tubularshaft portion 20 around the exterior of which a helical nave or flight21 is rigidly connected as by welding. The auger sections may be made inany suitable length which may be conveniently handled and transportedand are adapted to be connected together end to end so that a hole ofany desired or necessary depth may be drilled.

For coupling the auger sections to each other and to the cutting head,in order to assemble the auger string in operative condition so allsections will be rotated from the carriage 4, each auger section has areduced male portion of shank member 24 at one end for insertion into acorresponding female portion or socket member 25 in the other end of asimilar auger section. As shown in FIG. 5, each shank member 24 includesa circular cross section portion 27 that fits snugly within and iswelded to the tubular shaft portion 20 of an auger section. If desired,the intermediate part of portion '27 may be reduced in diameter as at 29to reduce weight, so that only the outer and inner ends 30 and 31 of theshank member are large enough to snugly fit within the interior of thetubular shaft portion 20.

The shank indicated at 24a is formed integrally at the outer end ofportion 27 and axially aligned therewith and preferably square incross-section as shown in FIG. 2 having flat inner walls 32 or may haveany other suitable non-circular cross sectional shape. A transverseopening 33 is formed in one of the walls 32 of the shank midway of itswidth, to receive the end of a latch bolt as will be described morefully below.

As shown in FIG. 5 the socket member 25 includes a cylindrical portion36 that fits snugly and is fixed within the tubular shaft'portion 20 ofthe auger section. The intermediate part of the cylindrical portion isalso reduced in diameter to save weight so only the outer and inner ends39 and 40 contact and are welded to the interior of tubular shaftportion 20. A longitudinal opening 42 of the cross sectional shape,preferably square, of the shank 24a and slightly larger in size extendsthrough the socket member; it has flat outer walls 42a.

The outer end-of the cylindrical portion of the shank member 24 and thesocket member 25 terminate in annular faces 43 and 44, respectively,preferably of about the same diameter as the exterior of the tubularshaft 20. The faces 43 and 44 are in contact when the shank and socketare mated as described below.

A latch assembly 45 extends radially through the wall of tubular shaftportion 20 and the cylindrical portion 36 of socket member 25 intosocket opening 42 (FIGS. 3 and 5). An aperture 46 is formed through onewall of shaft 20 and midway of the width of a flat wall 42a in socketmember 25 at the proper location to receive transverse through hole 50for a purpose described 5 below.

Housing 47 includes a cylindrical sleeve member 51 that fits snuglywithin aperture 46 and of the proper length to extend radially outwardlya short distance from the tubular shaft 20 when its inner end is alignedwith the outer wall 42a of the longitudinal opening 42 in socket member25. Sleeve member 51 is rigidly connected to shaft 20 preferably by.welding as at 54.

A compression type coil spring 56 fits within sleeve member 51 andsurrounds latch bolt 48. A disk 58 surrounds the lower end of latch bolt48 and seats against an annular shoulder 60 at the lower end of sleevemember 51, to provide a seat for the inner end of spring 56. A pinretainer member 62 is threaded into the outer end of sleeve member 51and when fully threaded slightly compresses spring 56.

Retainer member 62 includes a radially outwardly extending cylindricalportion having cut-outs therein to define radially extending slot 66 andconnected transversely extending slot 67, as shown in FIGS. 4 and 7.Latch bolt 48 carries a transversely extending pin that extends intoeither slot 66 or slot 67 according to whether latch bolt 48 is lockedor not as will be described below. Slot 66 is longer than slot 67radially of member 20, the length of the slots being such thattransverse pin 70 is free to move radially outwardly in slot 66 at leastthe distance that the inner end of latch bolt 48 (see FIG. 3) extendsinto the longitudinal opening 42 of socket member 25, and in slot 67substantially less than that distance. Latch bolt 48 is free to rotatewithin housing 47 within the limits defined by the extent of slots 66and 67 circumferentially of retainer. member 62.

Adjacent end opposing auger sections 3 are connected and latchedend-to-end by insertion of shank 25a of one section into thelongitudinal opening 42 of socket member 25 of the other section withthe wall 32 of the shank containing the opening 33 facing wall 42a untilannular faces 43 and 44 are in contact. Asshank 24 24a is inserted, itstapered forward face 72 contacts the inner end of latch bolt 48 and camsit radially outwardly against the biasing force of spring 56. When shank24a has completely entered longitudinal opening 42 the opening 33 in theshank is aligned with latch bolt' 48 and the latch bolt is urged by thecompressed spring 56 radially inwardly into the opening 33.

The auger sections 10 at this point are in the position 5 shown in FIG.4; that is, they are latched together but not locked together. A forcetending to pull apart the auger sections may have a component that willact upon latch bolt 48 and tend to force it radially outwardly out ofopening 33. Such a component, aided by centrifugal force produced byrotation of the auger assembly and acting to force latch bolt 48radially outwardly, may be sufficient to unlatch the auger sections andpermit them to come apart. Such a separation occurring while the augerassembly is within a drilled hole renders the auger string useless, asdescribed above, until the auger sections are reconnected.

The improved latch assembly of this invention, however, permits thelatch bolt 48 to be locked in opening 33, so that the auger sectionscannot be unintentionally disconnected.

Such locking is accomplished as shown in FIG. 6 by rotating the latchbolt 48 in the direction of the arrow until locking pin 70 passes fromslot 66 (the full line position) into slot 67 (the dotted lineposition). Such rotation may be facilitated by use of a lever or toolinserted through hole 50 in the radially outer end of latch bolt 48 andused to rotate the latch bolt.

At this point, the auger sections are not only latched together but alsoare locked together as shown in FIG. 7. The radial length of slot 67limits the radially outward movement of locking pin 70 and, therefore,also of latch bolt 48. In this position the auger sections 10 arelatched and locked together and cannot become disconnected without humanintervention.

It should also be noted that the inner wall of the transverse opening 33in shank 24a is tapered as shown at 74 in FIG. 5. This taper along withthe shape of the radially inner end 49 of latch bolt 48 tends to preventa force acting to pull apart the auger sections from developing acomponent that acts to push latch bolt 48 radially outwardly.

When a rearmost auger section is retracted from the drilled hole in thecoal seam, and it is desired to disconnect it from an adjacent forwardauger section, it is merely necessary to rotate latch bolt 48 of therearmost section to the position where locking pin 70 is positioned inradial slot 66, and then lift the latch bolt radially outwardly,preferably by a tool inserted in hole 50 in the projecting top portionof the latch bolt 48. The lower end of the latch bolt can thereafter bereadily withdrawn from opening 33 of shank 24a of the adjacent augersection by drawing upwardly on the tool in hole 50, and the shank 24amay be easily withdrawn from the longitudinal opening 42 of the rearmostauger section usually by retracting carriage 4. The rearmost augersection can then be disconnected from shaft 14 of carriage 4, removed,and the carriage advanced until it connects to the next auger section.The carriage can then be retracted, and the process repeated until allsections including the cutting head have been removed from the hole andthe machine.

While a preferred form of this invention has been shown and describedherein it will be apparent to those skilled in the art that variousmodifications may be made in the form herein disclosed without departingfrom the spirit and scope of the invention. Accordingly, the inventionis not to be limited to the form herein specifically disclosed anddescribed but only by the progress in the art which the invention haspromoted.

What is claimed is:

1. Apparatus for latching and locking together first and second augersections, said first auger section having an axially extending shank anda generally radially extending transverse opening in said shank, saidsecond auger section having a socket to receive said shank, saidapparatus comprising a housing for mounting on said second auger sectionto have its longitudinal axis extend transversely of said socket, saidhousing comprising a sleeve member adapted to be mounted to extendthrough the wall of said socket and a retainer member fixedly engagingsaid sleeve, a latch bolt having an axis and mounted in said housing andextending through said retainer member and said sleeve for reciprocablemovement along said axis and having an end protruding from said housingand adapted to extend into said transverse opening in said shank whensaid auger sections are connected, first and second slots in saidretainer member, said second slot extending generally axially of saidlatch bolt and said second slot being longer in said axial directionthan said first slot, a locking pin extending transversely from saidlatch bolt and into one of said slots, said latch bolt being rotatableabout its said axis to position said locking pin in one or the other ofsaid slots to limit the longitudinal movement of said latch bolt inaccordance with the length of the slot in which said locking pin ispositioned, the length of said first and second slots axially of saidlatch bolt being such that said locking pin is free to move in saidsecond slot at least the length of said protruding end of said latchbolt and in said first slot substantially less than the length of saidprotruding end, whereby the protruding end of said latch bolt may extendinto said transverse opening and may be locked therein or not inaccordance with whether said locking pin is positioned in said first orin said second slot.

2. Apparatus as claimed in claim 1 further comprising means biasing saidlatch bolt to cause its end to protrude from said housing.

3. Apparatus as claimed in claim 1, in which said latch bolt has anopposite end protruding from said housing, said opposite end providingmeans for rotating said latch bolt to move said locking pin into eitherof said slots.

4. Apparatus as claimed in claim 2, in which said latch bolt has anopposite end protruding from said housing, said opposite end providingmeans for rotating said latch bolt to move said locking pin into eitherof said slots, and to permit said latch bolt to be lifted so its firstmentioned protruding end can be removed from said first auger section.

5. In combination, a first auger section having an axially extendingshank having generally flat axially extending external surfaces defininga polygonal cross section, said shank having a generally radiallyextending transverse opening in one of said external surfaces, a secondauger section having an axially extending socket with a socket openingdefined by generally flat axially extending internal surfaces shaped toreceive and fit said shank and defining a socket wall of substantialthickness, said socket having a generally radially extending apertureextending through said wall and terminating in one of said internalsurfaces and aligned with said transverse opening, and means forlatching and locking said sections together comprising a housing on saidsocket and extending into said aperture for a major portion of thethickness of said wall, a latch bolt having an axis and supported insaid housing for reciprocable movement along said axis and having an endadapted to protrude into said transverse opening, first and secondinterconnected slots in said housing extending generally axially of saidlatch bolt, and a locking pin extending transversely from said latchbolt and into one of said slots, the length of said first and secondslots being such that said locking pin is free to move axially of saidlatch bolt in said second slot at least the length of said protrudingend of said latch bolt and in said first slot substantially less thanthe length of said protruding end, said latch bolt being rotatable insaid housing to position said locking pin in one or the other of saidslots to limit the movement of said latch bolt in accordance with thelength of the slot in which said locking pin is positioned, whereby saidlatch bolt is locked with its protruding end in said transverse openingor not in accordance with whether said locking pin is positioned in saidfirst or in said second slot.

6. The combination as claimed in claim comprising resilient meansbiasing said latch bolt to cause its end to protrude from said housingand extend into said transverse openrng. v

7. The combination as claimed in claim 6 comprising means on said latchbolt permitting it to be turned about its axis until its locking pin isaligned with said second slot and to be moved axially until itsprotruding end is moved out of said transverse opening.

8. In combination, a first auger section having an axially extendingshank having generally flat axially extending external surfaces defininga polygonal cross section, said shank having a generally radiallyextending transverse opening in one of said external surfaces, a secondauger section having an axially extending socket with a socket openingdefined by generally flat axially extending internal surfaces shaped toreceive and fit said shank, said socket having a generally radiallyextending aperture terminating in one of said internal surfaces andaligned with said transverse opening, and means for latching and lockingsaid sections together comprising a housing on said socket and alignedwith said aperture, a latch bolt having an axis and supported in saidhousing for reciprocable movement along said axis and having an endadapted to protrude into said transverse opening, first and secondinterconnected slots in said housing extending generally axially of saidlatch bolt, and a locking pin extending transversely from said latchbolt and into one of said slots, the length of said first and secondslots being such that said locking pin is free to move axially of saidlatch bolt in said second slot at least the length of said protrudingend of said latch bolt and in said first slot substantially less thanthe length of said protruding end, said latch bolt being rotatable insaid housing to position said locking pin in one or the other of saidslots to limit the movement of said latch bolt in accordance with thelength of the slot in which said locking pin is positioned, whereby saidlatch bolt is locked with its protruding end in said transverse openingor not in accordance with whether said locking pin is positioned in saidfirst or in said second slot, the protruding end of said latch bolt andthe walls of said transverse opening being tapered to prevent a forcetending to pull apart said auger sections from developing a componentthat acts to push said latch bolt radially outward out of saidtransverse opening.

9. The combination as claimed in claim 8 comprising resilient meansbiasing said latch bolt to cause its end to tending external surfacesdefining a polygonal cross section, said shank having a generallyradially extending transverse opening in one of said external surfaces,a second auger section having an axially extending socket with a socketopening defined by generally flat axially extending internal surfacesshaped to receive and fit said shank, said socket having a generallyradially extending aperture terminating in one of said internal surfacesand aligned with said transverse opening, and means for latching andlocking said sections together comprising a housing on said socket andaligned with said aperture, a latch bolt having an axis and supported insaid housingfor reciprocable movement along said axis and having an endadapted to protrude into said transverse opening,'first and secondinterconnected slots generally axially of said latch bolt, and a lockingpin extending transversely from said latch bolt and into one of saidslots, the length of said first and second slots being such that saidlocking pin is free to move axially of said latch bolt in said secondslot at least the length of said protruding end of said latch bolt andin said first slot substantially less than the length of said protrudingend, said latch bolt being rotatable in said housing to position saidlocking pin in one or the other of said slots to limit the movement ofsaid latch bolt in accordance with the length of the slot in which saidlocking pin is positioned, whereby said latch bolt is locked with itsprotruding end in said transverse opening or not in accordance withwhether said locking pin is positioned in said first or in said secondslot, said surface of said shank that contains said transverse openingand contacts the end of such latch bolt has its leading end tapered tocam said latch bolt axially thereof towards said radially extendingaperture in said socket as said shank is advanced into said socket. I

12. The combination as claimed in claim 11 comprising resilient meansbiasing said latch bolt to cause its end to protrude from said housingand extend into said transverse opening.

13. The combination as claimed in claim 1 l compris ing means on saidlatch bolt permitting it to be turned about its axis until its lockingpin is aligned with said second slot and to be moved axially until itsprotruding end is moved out of said transverse opening.

14. In combination, a first auger section having an axially extendingshank having generally flat'axially extending external surfaces defininga polygonal cross section, said shank having a generally radiallyextending transverse opening in one of said external surfaces, a secondauger section having an axially extending socket with a socket openingdefined by generally flat axially extending internal surfaces shaped toreceive and fit said shank, said socket having a generally radiallyextending aperture terminating in one of said internal surfaces andaligned with said transverse opening, and means for latching and lockingsaid sections together comprising a housing on said socket and in saidhousing extendingaligned wit said aperture, a latch bolt having an axisand supported in said housing for reciprocable movement along said axisand having an end adapted to protrude into said transverse opening,first and second interconnected slots in said housing extendinggenerally axially of said latch bolt, and a locking pin extendingtransversely from said latch bolt and into one of said slots, the lengthof said first and second slots being such that said locking pin is freeto move axially of said latch bolt in said second slot at least thelength of said protruding end of said latch bolt and in said first slotsubstantially less than the length of said protruding end, said latchbolt being rotatable in said housing to position said locking pin in oneor the other of said slots to limit the movement of said latch bolt inaccordance with the length of the slot in which said locking pin ispositioned, whereby said latch bolt is locked with its protruding end insaid transverse opening or not in accordance with whether said lockingpin is positioned in said first or in said second slot, said housingincluding a cylindrical sleeve member received within said aperture,said sleeve member having a threaded portion and a locking pin retainermember threadedly engaging said sleeve member, said latch bolt extendingthrough said pin retainer member and said sleeve member and having anend protruding from said sleeve member and into said transverse opening.

15. The combination as claimed in claim 14 comprising resilient meansbiasing said latch bolt to cause its end to protrude from said housingand extend into said transverse opening.

16. The combination as claimed in claim 14 comprising means on saidlatch bolt permitting it to be turned about its axis until its lockingpin is aligned with said second slot and to be moved axially until itsprotruding end is moved out of said transverse opening.

17. The combination as claimed in claim 14 wherein said first and secondslots are formed in said locking pin retainer member.

1. Apparatus for latching and locking together first and second auger sections, said first auger section having an axially extending shank and a generally radially extending transverse opening in said shank, said second auger section having a socket to receive said shank, said apparatus comprising a housing for mounting on said second auger section to have its longitudinal axis extend transversely of said socket, said housing comprising a sleeve member adapted to be mounted to extend through the wall of said socket and a retainer member fixedly engaging said sleeve, a latch bolt having an axis and mounted in said housing and extending through said retainer member and said sleeve for reciprocable movement along said axis and having an end protruding from said housing and adapted to extend into said transverse opening in said shank when said auger sections are connected, first and second slots in said retainer member, said second slot extending generally axially of said latch bolt and said second slot being longer in said axial direction than said first slot, a locking pin extending transversely from said latch bolt and into one of said slots, said latch bolt being rotatable about its said axis to position said locking pin in one or the other of said slots to limit the longitudinal movement of said latch bolt in accordance with the length of the slot in which said locking pin is positioned, the length of said first and second slots axially of said latch bolt being such that said locking pin is free to move in said second slot at least the length of said protruding end of said latch bolt and in said first slot substantially less than the length of said protruding end, whereby the protruding end of said latch bolt may extend into said transverse opening and may be locked therein or not in accordance with whether said locking pin is positioned in said first or in said second slot.
 2. Apparatus as claimed in claim 1 further comprising means biasing said latch bolt to cause its end to protrude from said housing.
 3. Apparatus as claimed in claim 1, in which said latch bolt has an opposite end protruding from said housing, said opposite end providing means for rotating said latch bolt to move said locking pin into either of said slots.
 4. Apparatus as claimed in claim 2, in which said latch bolt has an opposite end protruding from said housing, said opposite end providing means for rotating said latch bolt to move said locking pin into either of said slots, and to permit said latch bolt to be lifted so its first mentioned protruding end can be removed from said first auger section.
 5. In combination, a first auger section having an axially extending shank having generally flat axially extending external surfaces defining a polygonal cross section, said shank having a generally radially extending transverse opening in one of said external surfaces, a second auger section having an axially extending socket with a socket opening defined by generally flat axially extending internal surfaces shaped to receive and fit said shank and defining a socket wall of substantial thickness, said socket having a generally radially extending aperture extending through said wall and terminating in one of said internal surfaces and aligned with said transverse opening, and means for latching and locking said sections together comprising a housing on said socket and extending into said aperture for a major portion of the thickness of said wall, a latch bolt having an axis and supported in said housing for reciprocable movement along said axis and having an end adapted to protrude into said transverse opening, first and second interconnected slots in said housing extending generally axially of said latch bolt, and a locking pin extending transversely from said latch bolt and into one of said slots, the length of said first and second slots being such that said locking pin is free to move axially of said latch bolt in said second slot at least the length of said protruding end of said latch bolt and in said first slot substantially less than the length of said protruding end, said latch bolt being rotatable in said housing to position said locking pin in one or the other of said slots to limit the movement of said latch bolt in accordance with the length of the slot in which said locking pin is positioned, whereby said latch bolt is locked with its protruding end in said transverse opening or not in accordance with whether said locking pin is positioned in said first or in said second slot.
 6. The combination as claimed in claim 5 comprising resilient means biasing said latch bolt to cause its end to protrude from said housing and extend into said transverse opening.
 7. The combination as claimed in claim 6 comprising means on said latch bolt permitting it to be turned about its axis until its locking pin is aligned with said second slot and to be moved axially until its protruding end is moved out of said transverse opening.
 8. In combination, a first auger section having an axially extending shank having generally flat axially extending external surfaces defining a polygonal cross section, said shank having a generally radially extending transverse opening in one of said external surfaces, a second auger section having an axially extending socket with a socket opening defined by generally flat axially extending internal surfaces shaped to receive and fit said shank, said socket having a generally radially extending aperture terminating in one of said internal surfaces and aligned with said transverse opening, and means for latching and locking said sections together comprising a housing on said socket and aligned with said aperture, a latch bolt having an axis and supported in said housing for reciprocable movement along said axis and having an end adapted to protrude into said transverse opening, first and second interconnected slots in said housing extending generally axially of said latch bolt, and a locking pin extending transversely from said latch bolt and into one of said slots, the length of said first and second slots being such that said locking pin is free to move axially of said latch bolt in said second slot at least the length oF said protruding end of said latch bolt and in said first slot substantially less than the length of said protruding end, said latch bolt being rotatable in said housing to position said locking pin in one or the other of said slots to limit the movement of said latch bolt in accordance with the length of the slot in which said locking pin is positioned, whereby said latch bolt is locked with its protruding end in said transverse opening or not in accordance with whether said locking pin is positioned in said first or in said second slot, the protruding end of said latch bolt and the walls of said transverse opening being tapered to prevent a force tending to pull apart said auger sections from developing a component that acts to push said latch bolt radially outward out of said transverse opening.
 9. The combination as claimed in claim 8 comprising resilient means biasing said latch bolt to cause its end to protrude from said housing and extend into said transverse opening.
 10. The combination as claimed in claim 8 comprising means on said latch bolt permitting it to be turned about its axis until its locking pin is aligned with said second slot and to be moved axially until its protruding end is moved out of said transverse opening.
 11. In combination, a first auger section having an axially extending shank having generally flat axially extending external surfaces defining a polygonal cross section, said shank having a generally radially extending transverse opening in one of said external surfaces, a second auger section having an axially extending socket with a socket opening defined by generally flat axially extending internal surfaces shaped to receive and fit said shank, said socket having a generally radially extending aperture terminating in one of said internal surfaces and aligned with said transverse opening, and means for latching and locking said sections together comprising a housing on said socket and aligned with said aperture, a latch bolt having an axis and supported in said housing for reciprocable movement along said axis and having an end adapted to protrude into said transverse opening, first and second interconnected slots in said housing extending generally axially of said latch bolt, and a locking pin extending transversely from said latch bolt and into one of said slots, the length of said first and second slots being such that said locking pin is free to move axially of said latch bolt in said second slot at least the length of said protruding end of said latch bolt and in said first slot substantially less than the length of said protruding end, said latch bolt being rotatable in said housing to position said locking pin in one or the other of said slots to limit the movement of said latch bolt in accordance with the length of the slot in which said locking pin is positioned, whereby said latch bolt is locked with its protruding end in said transverse opening or not in accordance with whether said locking pin is positioned in said first or in said second slot, said surface of said shank that contains said transverse opening and contacts the end of such latch bolt has its leading end tapered to cam said latch bolt axially thereof towards said radially extending aperture in said socket as said shank is advanced into said socket.
 12. The combination as claimed in claim 11 comprising resilient means biasing said latch bolt to cause its end to protrude from said housing and extend into said transverse opening.
 13. The combination as claimed in claim 11 comprising means on said latch bolt permitting it to be turned about its axis until its locking pin is aligned with said second slot and to be moved axially until its protruding end is moved out of said transverse opening.
 14. In combination, a first auger section having an axially extending shank having generally flat axially extending external surfaces defining a polygonal cross section, said shank having a generally radially extending transverse opening in one of said external surfaces, a second auger section having an axially extending socket with a socket opening defined by generally flat axially extending internal surfaces shaped to receive and fit said shank, said socket having a generally radially extending aperture terminating in one of said internal surfaces and aligned with said transverse opening, and means for latching and locking said sections together comprising a housing on said socket and aligned with said aperture, a latch bolt having an axis and supported in said housing for reciprocable movement along said axis and having an end adapted to protrude into said transverse opening, first and second interconnected slots in said housing extending generally axially of said latch bolt, and a locking pin extending transversely from said latch bolt and into one of said slots, the length of said first and second slots being such that said locking pin is free to move axially of said latch bolt in said second slot at least the length of said protruding end of said latch bolt and in said first slot substantially less than the length of said protruding end, said latch bolt being rotatable in said housing to position said locking pin in one or the other of said slots to limit the movement of said latch bolt in accordance with the length of the slot in which said locking pin is positioned, whereby said latch bolt is locked with its protruding end in said transverse opening or not in accordance with whether said locking pin is positioned in said first or in said second slot, said housing including a cylindrical sleeve member received within said aperture, said sleeve member having a threaded portion and a locking pin retainer member threadedly engaging said sleeve member, said latch bolt extending through said pin retainer member and said sleeve member and having an end protruding from said sleeve member and into said transverse opening.
 15. The combination as claimed in claim 14 comprising resilient means biasing said latch bolt to cause its end to protrude from said housing and extend into said transverse opening.
 16. The combination as claimed in claim 14 comprising means on said latch bolt permitting it to be turned about its axis until its locking pin is aligned with said second slot and to be moved axially until its protruding end is moved out of said transverse opening.
 17. The combination as claimed in claim 14 wherein said first and second slots are formed in said locking pin retainer member. 